object ClubErrorDemoFixed {
  def main(args: Array[String]): Unit = {
    var members = Set("张三", "李四", "张三")
    val activities = List("1月活动","2月活动","3月活动")
    val total = members.size
    println(s"总人数：$total")
    println("活动顺序：")
    activities.foreach(println)
  }
}
